JP6789148B2 - Damper valve and damper - Google Patents

Description

この発明は、減衰弁およびダンパに関する。 The present invention relates to damping valves and dampers.

免震装置は、地盤と構造物との間に介装されるボールアイソレータやゴムといった支持装置を備え、構造物を地盤に対して変位可能に支持しており、地震動の構造物への伝達を絶縁するようになっている。免震装置には、前記のような支持装置の他に、地盤と構造物との間に介装されるダンパを備える場合もあり、構造物の振動をダンパが発生する減衰力で減衰させて構造物の振動を抑制するようになっている。 The seismic isolation device is equipped with a support device such as a ball isolator or rubber that is interposed between the ground and the structure, supports the structure in a displaceable manner with respect to the ground, and transmits the seismic motion to the structure. It is designed to be insulated. In addition to the support device as described above, the seismic isolation device may be provided with a damper interposed between the ground and the structure, and the vibration of the structure is damped by the damping force generated by the damper. It is designed to suppress the vibration of the structure.

このように免震装置に併用される免震用のダンパは、構造物の振動を抑制できるが、ピストン速度が高速域に達する大きな揺れに対してダンパの減衰力が過大となると構造物に大きな加速度が作用して柱や梁などが変形してしまう可能性がある。 In this way, the seismic isolation damper used together with the seismic isolation device can suppress the vibration of the structure, but if the damping force of the damper becomes excessive against the large vibration that the piston speed reaches the high speed range, it will be large for the structure. There is a possibility that columns and beams will be deformed due to the action of acceleration.

よって、免震用のダンパにあっては、調圧弁とリリーフ弁を並列して構成された減衰弁を備えており、図６に示すように、ピストン速度が速くなるとリリーフ弁が開弁して減衰係数を小さくして、高速時における減衰力が過多となるのを防止し、構造物の保護を図っている（たとえば、特許文献１参照）。 Therefore, the seismic isolation damper is equipped with a damping valve configured by arranging a pressure regulating valve and a relief valve in parallel, and as shown in FIG. 6, the relief valve opens when the piston speed increases. The damping coefficient is reduced to prevent the damping force from becoming excessive at high speeds, and the structure is protected (see, for example, Patent Document 1).

特開２００５−２４８５２０号公報Japanese Unexamined Patent Publication No. 2005-248520

しかしながら、前述の減衰弁では、免震装置の免震効果を阻害してしまう場合がある。前述の減衰弁を利用したダンパの減衰力特性（ピストン速度に対してダンパが発生する減衰力の特性）は、減衰係数が小さく切り換わるまでは、つまり、リリーフ弁が開弁するまでは、調圧弁の減衰係数が大きくピストン速度の増加に対して減衰力の増加量も大きい特性となる。 However, the above-mentioned damping valve may hinder the seismic isolation effect of the seismic isolation device. The damping force characteristic of the damper using the damping valve (characteristic of the damping force generated by the damper with respect to the piston speed) is adjusted until the damping coefficient is switched to a small value, that is, until the relief valve is opened. The damping coefficient of the pressure valve is large, and the amount of increase in damping force is large with respect to the increase in piston speed.

すると、ピストン速度が低速域にあってもダンパが発生する減衰力が過多となって、地震動を構造物に伝達してしまい免震装置の免震効果を阻害してしまう場合がある。 Then, even if the piston speed is in the low speed range, the damping force generated by the damper becomes excessive, and the seismic motion is transmitted to the structure, which may hinder the seismic isolation effect of the seismic isolation device.

そうかと言って、リリーフ弁が開弁するまでは減衰係数を低くして免震効果を得ようとすると、以下の問題が生じる。具体的には、大振幅の地震動が発生した場合に、今度は減衰力不足に陥りダンパが最伸長或いは最収縮するか、或いは、構造物が地盤に対する構造物の変位を抑制するストッパに衝突して、構造物に衝撃的な加速度を作用させてしまう可能性がある。 On the other hand, if the damping coefficient is lowered until the relief valve is opened to obtain the seismic isolation effect, the following problems occur. Specifically, when a large-amplitude seismic motion occurs, the damping force is insufficient and the damper is fully extended or contracted, or the structure collides with a stopper that suppresses the displacement of the structure with respect to the ground. Therefore, there is a possibility that a shocking acceleration is applied to the structure.

そこで、本発明は前記問題を解決するために創案されたものであって、その目的は、免震効果を損なわず、ピストン速度が高速域に達する大振幅の地震動に対して高い減衰力をダンパに発揮させる減衰弁の提供である。また、他の目的は、免震効果を損なわず、ピストン速度が高速域に達する大振幅の地震動に対して高い減衰力を発揮可能なダンパの提供である。 Therefore, the present invention was devised to solve the above problems, and an object thereof is to damper a high damping force against a large-amplitude seismic motion in which the piston speed reaches a high speed range without impairing the seismic isolation effect. It is the provision of a damping valve that can be exerted on the ground. Another object is to provide a damper capable of exerting a high damping force against a large-amplitude seismic motion in which the piston speed reaches a high speed range without impairing the seismic isolation effect.

前記した目的を達成するために、本発明の減衰弁は、低圧力損失弁と、低圧力損失弁と並列に設けられて低圧力損失弁より圧力損失が大きいノーマルクローズ型の高圧力損失弁とを備えており、低圧力損失弁が上流の圧力の上昇に伴って閉弁する。このように構成された減衰弁をダンパに適用すると、小規模地震動の発生時にはダンパが発生する減衰力が小さくなり、大規模地震動の発生時にはダンパが大きな減衰力を発揮するようになる。 In order to achieve the above object, the damping valve of the present invention includes a low pressure loss valve and a normally closed type high pressure loss valve which is provided in parallel with the low pressure loss valve and has a larger pressure loss than the low pressure loss valve. The low pressure drop valve closes as the upstream pressure rises. When the damping valve configured in this way is applied to the damper, the damping force generated by the damper becomes small when a small-scale earthquake motion occurs, and the damper exerts a large damping force when a large-scale earthquake motion occurs.

また、高圧力損失弁が低圧力損失弁の閉弁とともに開弁するように減衰弁を構成してもよい。このように構成された減衰弁をダンパに適用すれば、ダンパの減衰係数を設定圧に対応するピストン速度で切換でき、免震装置の設計が非常に容易となる。 Further, the damping valve may be configured so that the high pressure loss valve opens together with the closing of the low pressure loss valve. If the damping valve configured in this way is applied to the damper, the damping coefficient of the damper can be switched at the piston speed corresponding to the set pressure, and the design of the seismic isolation device becomes very easy.

さらに、高圧力損失弁の開弁圧を前記低圧力損失弁の開弁圧よりも高く、前記低圧力損失弁の閉弁圧よりも低い圧力に設定して、低圧力損失弁が閉弁するより前に高圧力損失弁が開弁するように減衰弁を構成してもよい。このように構成された減衰弁をダンパに適用すれば、減衰係数の切換時において減衰力の変化が滑らかとなるので、免震装置に利用しても構造物へ衝撃を与えずに済む。 Further, the valve opening pressure of the high pressure loss valve is set to be higher than the valve opening pressure of the low pressure loss valve and lower than the valve closing pressure of the low pressure loss valve, and the low pressure loss valve is closed. The damping valve may be configured so that the high pressure drop valve opens earlier. If the damping valve configured in this way is applied to the damper, the change in the damping force becomes smooth when the damping coefficient is switched, so that even if it is used as a seismic isolation device, it does not give an impact to the structure.

また、高圧力損失弁が低圧力損失弁の閉弁の際に、低圧力損失弁を通過していた流量を補償するように減衰弁を構成してもよい。このように構成された減衰弁をダンパに適用すれば、減衰係数の切換時において減衰力が急峻に変化しないので、免震装置に利用しても構造物へ衝撃を与えずに済む。 Further, the damping valve may be configured so that the high pressure loss valve compensates for the flow rate passing through the low pressure loss valve when the low pressure loss valve is closed. If the damping valve configured in this way is applied to the damper, the damping force does not change sharply when the damping coefficient is switched, so that even if it is used as a seismic isolation device, it does not give an impact to the structure.

さらに、ダンパは、シリンダと、シリンダ内に移動自在に挿入されたピストンと、シリンダ内にピストンで区画した伸側室と圧側室と、リザーバと、減衰弁とを備えて構成してもよい。このように構成されたダンパでは、免震効果を損なわず、ピストン速度が高速域に達する大振幅の地震動に対して高い減衰力を発揮できる。 Further, the damper may be configured to include a cylinder, a piston movably inserted into the cylinder, an extension side chamber and a compression side chamber partitioned by the piston in the cylinder, a reservoir, and a damping valve. The damper configured in this way can exert a high damping force against a large-amplitude seismic motion in which the piston speed reaches a high speed range without impairing the seismic isolation effect.

よって、本発明の減衰弁によれば、免震効果を損なわず、ピストン速度が高速域に達する大振幅の地震動に対して高い減衰力をダンパに発揮させえる。また、本発明のダンパによれば、免震効果を損なわず、ピストン速度が高速域に達する大振幅の地震動に対して高い減衰力を発揮できる。 Therefore, according to the damping valve of the present invention, a high damping force can be exerted on the damper against a large-amplitude seismic motion in which the piston speed reaches a high speed range without impairing the seismic isolation effect. Further, according to the damper of the present invention, a high damping force can be exhibited against a large-amplitude seismic motion in which the piston speed reaches a high speed range without impairing the seismic isolation effect.

一実施の形態における減衰弁の断面図である。It is sectional drawing of the damping valve in one Embodiment. 一実施の形態の一変形例における減衰弁の断面図である。It is sectional drawing of the damping valve in one modification of one Embodiment. 一実施の形態における減衰弁の圧力流量特性を示した図である。It is a figure which showed the pressure flow rate characteristic of the damping valve in one Embodiment. 一実施の形態の減衰弁を適用したダンパの回路図である。It is a circuit diagram of the damper to which the damping valve of one Embodiment is applied. 一実施の形態の減衰弁を適用したダンパの減衰力特性を示した図である。It is a figure which showed the damping force characteristic of the damper to which the damping valve of one Embodiment was applied. 従来の免震用のダンパの減衰力特性を示した図である。It is a figure which showed the damping force characteristic of the damper for the conventional seismic isolation.

以下に、図示した実施の形態に基づいて、この発明を説明する。一実施の形態における減衰弁Ｖは、図１に示すように、低圧力損失弁ＶＬと、低圧力損失弁ＶＬと並列に設けた高圧力損失弁ＶＨとを備えて構成されている。 The present invention will be described below based on the illustrated embodiments. As shown in FIG. 1, the damping valve V in one embodiment includes a low pressure loss valve VL and a high pressure loss valve VH provided in parallel with the low pressure loss valve VL.

以下、減衰弁Ｖについて説明する。低圧力損失弁ＶＬおよび高圧力損失弁ＶＨは、図１に示したように、ハウジングＨに設けた弁孔ｈ１，ｈ２に収容されている。ハウジングＨは、図１中右方の上流側の部屋Ａと図１中左方の下流側の部屋Ｂの仕切りとして機能しており、弁孔ｈ１，ｈ２は、ハウジングＨを貫通して、部屋Ａと部屋Ｂとを連通している。 Hereinafter, the damping valve V will be described. As shown in FIG. 1, the low pressure loss valve VL and the high pressure loss valve VH are housed in the valve holes h1 and h2 provided in the housing H. The housing H functions as a partition between the room A on the upstream side on the right side in FIG. 1 and the room B on the downstream side on the left side in FIG. 1, and the valve holes h1 and h2 penetrate the housing H to form a room. A and room B are connected.

弁孔ｈ１は、部屋Ａ側から開口部１と、開口部１の内径よりも内径が小径な小径部２、小径部２の内径より大きな内径を持つ大径部３および大径部３の内径より大きな内径を持つとともに内周に螺子溝が設けられる螺子部４を備えるとともに、小径部２と大径部３との境に段部５を備える。他方の弁孔ｈ２は、部屋Ａ側から小径部６、小径部６の内径より大きな内径を持つ大径部７および大径部７の内径より大きな内径を持つとともに内周に螺子溝が設けられる螺子部８を備えるとともに、小径部６と大径部７との境に段部９を備える。 The valve hole h1 has an opening 1 from the room A side, a small diameter portion 2 having an inner diameter smaller than the inner diameter of the opening 1, a large diameter portion 3 having an inner diameter larger than the inner diameter of the small diameter portion 2, and an inner diameter portion 3 of the large diameter portion 3. A screw portion 4 having a larger inner diameter and a screw groove provided on the inner circumference is provided, and a step portion 5 is provided at the boundary between the small diameter portion 2 and the large diameter portion 3. The other valve hole h2 has an inner diameter larger than the inner diameter of the small diameter portion 6, the large diameter portion 7 having an inner diameter larger than the inner diameter of the small diameter portion 6, and the inner diameter portion 7 from the chamber A side, and is provided with a screw groove on the inner circumference. A screw portion 8 is provided, and a step portion 9 is provided at the boundary between the small diameter portion 6 and the large diameter portion 7.

低圧力損失弁ＶＬは、図１に示すように、弁孔ｈ１の開口部１から大径部３にかけて軸方向移動自在に挿入される弁体１０と、弁体１０を附勢するばね１１と、螺子部４に螺子締結される環状のばね受１２とを備えて構成されている。 As shown in FIG. 1, the low pressure loss valve VL includes a valve body 10 inserted so as to be movable in the axial direction from the opening 1 of the valve hole h1 to the large diameter portion 3, and a spring 11 for encouraging the valve body 10. , An annular spring receiver 12 screwed to the screw portion 4 is provided.

弁体１０は、小径部２内に摺動自在に挿入されるガイド軸１０ａと、ガイド軸１０ａより図１中左方に連なる円盤状の弁頭１０ｂと、弁頭１０ｂの図１中左方の背面側に設けた軸上のばねガイド１０ｃと、ガイド軸１０ａの先端に設けたストッパ１０ｄと、ガイド軸１０ａの側部に軸方向に沿って設けたオリフィス溝１０ｅとを備えて構成されている。 The valve body 10 has a guide shaft 10a slidably inserted into the small diameter portion 2, a disk-shaped valve head 10b connected to the left side in FIG. 1 from the guide shaft 10a, and a valve head 10b on the left side in FIG. The spring guide 10c on the shaft provided on the back side of the guide shaft 10a, the stopper 10d provided at the tip of the guide shaft 10a, and the orifice groove 10e provided on the side portion of the guide shaft 10a along the axial direction are provided. There is.

弁体１０は、ガイド軸１０ａが小径部２に摺動自在に挿入されているので、軸ぶれせずに弁孔ｈ１内を軸方向へ移動できる。また、弁頭１０ｂが弁孔ｈ１の段部５に当接すると、低圧力損失弁ＶＬは閉弁する。ばね１１は、ばねガイド１０ｃの外周に装着されるとともに、弁頭１０ｂの背面とばね受１２との間で介装されており、弁体１０を図１中右方へ附勢している。よって、部屋Ａと部屋Ｂの圧力に差がない状態では、弁体１０がばね１１によって附勢されて弁頭１０ｂが段部５に当接する閉弁位置に配置されて、低圧力損失弁ＶＬは閉弁状態となる。 Since the guide shaft 10a is slidably inserted into the small diameter portion 2 of the valve body 10, the valve body 10 can move in the valve hole h1 in the axial direction without shaft deviation. Further, when the valve head 10b comes into contact with the step portion 5 of the valve hole h1, the low pressure loss valve VL closes. The spring 11 is mounted on the outer circumference of the spring guide 10c and is interposed between the back surface of the valve head 10b and the spring receiver 12, and the valve body 10 is urged to the right in FIG. Therefore, when there is no difference in pressure between the chamber A and the chamber B, the valve body 10 is biased by the spring 11 and the valve head 10b is arranged at the valve closing position where the valve head 10b abuts on the step portion 5, and the low pressure loss valve VL Is closed.

また、オリフィス溝１０ｅの全長は、小径部２の軸方向長さより長く、弁体１０が後退して弁頭１０ｂが段部５から離間するとガイド軸１０ａに設けたオリフィス溝１０ｅを介して大径部３内が部屋Ａに通じる。弁体１０には、部屋Ａの圧力が作用しており、部屋Ａの圧力が部屋Ｂの圧力より高くなると弁体１０が図１中左方へ押圧される。そして、部屋Ａの圧力によって弁体１０が図１中左方へ押圧されて、ばね１１の附勢力に抗して弁頭１０ｂが段部５から離間すると低圧力損失弁ＶＬは開弁し、オリフィス溝１０ｅを通じて部屋Ａと部屋Ｂとを連通する。 Further, the total length of the orifice groove 10e is longer than the axial length of the small diameter portion 2, and when the valve body 10 retracts and the valve head 10b is separated from the step portion 5, the large diameter is passed through the orifice groove 10e provided in the guide shaft 10a. The inside of part 3 leads to room A. The pressure of the room A acts on the valve body 10, and when the pressure of the room A becomes higher than the pressure of the room B, the valve body 10 is pressed to the left in FIG. Then, when the valve body 10 is pressed to the left in FIG. 1 by the pressure of the chamber A and the valve head 10b is separated from the step portion 5 against the urging force of the spring 11, the low pressure loss valve VL is opened. Room A and room B are communicated with each other through the orifice groove 10e.

さらに、弁体１０が閉弁位置から図１中左方へ後退して、弁頭１０ｂが段部５から所定距離離間すると、ストッパ１０ｄが開口部１の底部に当接して、弁体１０のそれ以上の後退を規制するとともにオリフィス溝１０ｅと部屋Ａとの連通が絶たれる。このように、本例の低圧力損失弁ＶＬは、部屋Ａの圧力が部屋Ｂの圧力より大きくなると開弁し、部屋Ａの圧力の上昇に伴って、部屋Ａの圧力と部屋Ｂの圧力の差圧が設定圧以上となると閉弁する。弁体１０に部屋Ａの圧力と部屋Ｂの圧力が正面と背面とに作用するため、低圧力損失弁ＶＬにおける閉弁圧は、部屋Ａの圧力と部屋Ｂの圧力の差圧に依存して決され、本例では前記設定圧とされている。 Further, when the valve body 10 retracts from the valve closing position to the left in FIG. 1 and the valve head 10b is separated from the step portion 5 by a predetermined distance, the stopper 10d comes into contact with the bottom portion of the opening 1 and the valve body 10 Further retreat is restricted and the communication between the orifice groove 10e and the room A is cut off. As described above, the low pressure loss valve VL of this example opens when the pressure in the room A becomes larger than the pressure in the room B, and as the pressure in the room A rises, the pressure in the room A and the pressure in the room B increase. The valve closes when the differential pressure exceeds the set pressure. Since the pressure of the room A and the pressure of the room B act on the valve body 10 on the front surface and the back surface, the valve closing pressure in the low pressure loss valve VL depends on the differential pressure between the pressure of the room A and the pressure of the room B. It is determined, and in this example, it is the set pressure.

なお、図２に示す低圧力損失弁ＶＬのように、ストッパを弁体の背面側に設けて閉弁させるようにしてもよい。図２に示す低圧力損失弁ＶＬでは、図１に示した低圧力損失弁ＶＬにおける弁体１０からストッパ１０ｄを廃止してばね受１２に筒状のストッパ１２ａを設けて、弁体１０の最大リフト量を設定してオリフィス溝１０ｅが小径部２によって閉塞されるようにしてある。具体的には、図２の低圧力損失弁ＶＬでは、ばね受１２に弁体１０側へ突出する筒状のストッパ１２ａを設けてあり、弁体１０が段部５から所定量離間すると弁頭１０ｂがストッパ１２ａに当接して、それ以上の弁体１０の段部５から離間するのを規制している。つまり、弁体１０が段部５から遠ざかる最大リフト量がストッパ１２ａによって設定されている。そして、弁体１０がストッパ１２ａに当接して段部５からの離間が規制されるとオリフィス溝１０ｅの先端である図２中右端が小径部２に対向して、オリフィス溝１０ｅを通じての部屋Ａと部屋Ｂとの連通が絶たれて、低圧力損失弁ＶＬが閉弁する。このように低圧力損失弁ＶＬを構成しても、部屋Ａの圧力の上昇に伴って、部屋Ａの圧力と部屋Ｂの圧力の差圧が設定圧以上となると閉弁するように構成できる。 In addition, like the low pressure loss valve VL shown in FIG. 2, a stopper may be provided on the back side of the valve body to close the valve. In the low pressure loss valve VL shown in FIG. 2, the stopper 10d is abolished from the valve body 10 in the low pressure loss valve VL shown in FIG. 1, and the spring receiver 12 is provided with a tubular stopper 12a to maximize the valve body 10. The lift amount is set so that the orifice groove 10e is closed by the small diameter portion 2. Specifically, in the low pressure loss valve VL of FIG. 2, the spring receiver 12 is provided with a tubular stopper 12a protruding toward the valve body 10, and when the valve body 10 is separated from the step portion 5 by a predetermined amount, the valve head It is restricted that the 10b abuts on the stopper 12a and further separates from the step portion 5 of the valve body 10. That is, the maximum lift amount at which the valve body 10 moves away from the step portion 5 is set by the stopper 12a. Then, when the valve body 10 comes into contact with the stopper 12a and the separation from the step portion 5 is restricted, the right end in FIG. 2, which is the tip of the orifice groove 10e, faces the small diameter portion 2, and the room A passes through the orifice groove 10e. The communication between the valve and the room B is cut off, and the low pressure loss valve VL is closed. Even if the low pressure loss valve VL is configured in this way, it can be configured to close when the differential pressure between the pressure in the room A and the pressure in the room B becomes equal to or higher than the set pressure as the pressure in the room A rises.

他方、高圧力損失弁ＶＨは、図１に示すように、弁孔ｈ２の小径部６から大径部７にかけて軸方向移動自在に挿入される弁体１３と、弁体１３を附勢するばね１４と、螺子部８に螺子締結される環状のばね受１５とを備えて構成され、ノーマルクローズ型の弁とされている。 On the other hand, as shown in FIG. 1, the high pressure loss valve VH has a valve body 13 inserted so as to be movable in the axial direction from the small diameter portion 6 to the large diameter portion 7 of the valve hole h2, and a spring for encouraging the valve body 13. 14 and an annular spring receiver 15 screwed to the screw portion 8 are provided, and the valve is a normally closed type valve.

弁体１３は、小径部６内に摺動自在に挿入されるガイド軸１３ａと、ガイド軸１３ａより図１中左方に連なる円盤状の弁頭１３ｂと、弁頭１３ｂの図１中左方の背面側に設けた軸上のばねガイド１３ｃと、ガイド軸１３ａの側部に軸方向に沿って設けたオリフィス溝１３ｄとを備えて構成されている。 The valve body 13 has a guide shaft 13a slidably inserted into the small diameter portion 6, a disk-shaped valve head 13b connected to the left side in FIG. 1 from the guide shaft 13a, and a valve head 13b on the left side in FIG. The spring guide 13c on the shaft provided on the back side of the guide shaft 13a and the orifice groove 13d provided on the side portion of the guide shaft 13a along the axial direction are provided.

弁体１３は、ガイド軸１３ａが小径部６に摺動自在に挿入されているので、軸ぶれせずに弁孔ｈ２内を軸方向へ移動できる。また、弁頭１３ｂが弁孔ｈ２の段部９に当接すると、高圧力損失弁ＶＨは閉弁する。ばね１４は、ばねガイド１３ｃの外周に装着されるとともに、弁頭１３ｂの背面とばね受１５との間で介装されており、弁体１３を図１中右方へ附勢している。よって、部屋Ａと部屋Ｂの圧力に差がない状態では、弁体１３がばね１４によって附勢されて弁頭１３ｂが段部９に当接する閉弁位置に配置されて、高圧力損失弁ＶＨは閉弁状態となる。 Since the guide shaft 13a is slidably inserted into the small diameter portion 6 of the valve body 13, the valve body 13 can move in the valve hole h2 in the axial direction without shaft deviation. Further, when the valve head 13b comes into contact with the step portion 9 of the valve hole h2, the high pressure loss valve VH is closed. The spring 14 is mounted on the outer periphery of the spring guide 13c and is interposed between the back surface of the valve head 13b and the spring receiver 15, and the valve body 13 is urged to the right in FIG. Therefore, when there is no difference in pressure between the chamber A and the chamber B, the valve body 13 is biased by the spring 14 and the valve head 13b is arranged at the valve closing position where the valve head 13b abuts on the step portion 9, and the high pressure loss valve VH Is closed.

また、オリフィス溝１３ｄは、ガイド軸１３ａの全長に亘って設けられており、弁体１３が後退して弁頭１３ｂが段部９から離間するとガイド軸１３ａに設けたオリフィス溝１３ｄを介して大径部７内が部屋Ａに通じる。弁体１３には、部屋Ａの圧力が作用しており、部屋Ａの圧力が部屋Ｂの圧力より高く両者の差圧が設定圧以上となると弁体１３が図１中左方へ押圧されて、ばね１４の附勢力に抗して弁頭１３ｂが段部９から離間する。つまり、高圧力損失弁ＶＨは、部屋Ａの圧力と部屋Ｂの圧力の差圧が設定圧以上となると開弁して、オリフィス溝１３ｄを通じて部屋Ａと部屋Ｂとを連通する。弁体１３に部屋Ａの圧力と部屋Ｂの圧力が正面と背面とに作用するため、高圧力損失弁ＶＨにおける開弁圧は、部屋Ａの圧力と部屋Ｂの圧力の差圧に依存して決され、本例では前記設定圧とされている。この開弁圧である設定圧は、ばね１４に与える初期荷重によって設定すればよい。また、オリフィス溝１３ｄをガイド軸１３ａの全長に亘って設けるのではなく、オリフィス溝１３ｄをガイド軸１３ａの図１中左端まで設けず、弁頭１３ｂが段部９から少し離間してからオリフィス溝１３ｄが大径部７に連通されるようにしてもよい。 Further, the orifice groove 13d is provided over the entire length of the guide shaft 13a, and when the valve body 13 retracts and the valve head 13b is separated from the step portion 9, the orifice groove 13d is large through the orifice groove 13d provided in the guide shaft 13a. The inside of the diameter portion 7 leads to the room A. The pressure of the room A acts on the valve body 13, and when the pressure of the room A is higher than the pressure of the room B and the differential pressure between the two becomes equal to or higher than the set pressure, the valve body 13 is pressed to the left in FIG. , The valve head 13b is separated from the step portion 9 against the urging force of the spring 14. That is, the high pressure loss valve VH opens when the differential pressure between the pressure in the room A and the pressure in the room B becomes equal to or higher than the set pressure, and communicates the room A and the room B through the orifice groove 13d. Since the pressure of the room A and the pressure of the room B act on the valve body 13 on the front surface and the back surface, the valve opening pressure in the high pressure loss valve VH depends on the differential pressure between the pressure of the room A and the pressure of the room B. It is determined, and in this example, it is the set pressure. The set pressure, which is the valve opening pressure, may be set according to the initial load applied to the spring 14. Further, instead of providing the orifice groove 13d over the entire length of the guide shaft 13a, the orifice groove 13d is not provided up to the left end in FIG. 1 of the guide shaft 13a, and the orifice groove 13b is slightly separated from the step portion 9. The 13d may be communicated with the large diameter portion 7.

本例では、前述したように、低圧力損失弁ＶＬの閉弁圧と高圧力損失弁ＶＨの開弁圧が前記設定圧となっている。よって、図３に示すように、低圧力損失弁ＶＬと高圧力損失弁ＶＨの合成圧力流量特性は、設定圧Ｐｓ未満の範囲では低圧力損失弁ＶＬの特性が表れ、設定圧Ｐｓ超の範囲では高圧力損失弁ＶＨの特性が表れる。流量の観点からは、減衰弁Ｖを通過する流量が流量Ｑｓに達すると、部屋Ａと部屋Ｂの差圧が設定圧Ｐｓとなり、流量増加に伴って流量Ｑｓを境にして低圧力損失弁ＶＬの特性から高圧力損失弁ＶＨの特性へ遷移する。また、高圧力損失弁ＶＨは、低圧力損失弁ＶＬに比較して同流量の作動油が通過する際の圧力損失が大きい。よって、減衰弁Ｖの圧力流量特性、つまり、低圧力損失弁ＶＬと高圧力損失弁ＶＨの合成圧力流量特性は、図３に示すように、低圧力損失弁ＶＬの特性が表れる範囲から高圧力損失弁ＶＨの特性が現れる範囲に移行すると、圧力流量特性の傾きが大きくなる。 In this example, as described above, the valve closing pressure of the low pressure loss valve VL and the valve opening pressure of the high pressure loss valve VH are the set pressures. Therefore, as shown in FIG. 3, the combined pressure flow rate characteristics of the low pressure loss valve VL and the high pressure loss valve VH show the characteristics of the low pressure loss valve VL in the range of less than the set pressure Ps, and in the range of exceeding the set pressure Ps. Then, the characteristics of the high pressure loss valve VH appear. From the viewpoint of flow rate, when the flow rate passing through the damping valve V reaches the flow rate Qs, the differential pressure between the room A and the room B becomes the set pressure Ps, and as the flow rate increases, the low pressure loss valve VL is separated from the flow rate Qs. Transition from the characteristic of the high pressure loss valve VH to the characteristic of the high pressure loss valve VH. Further, the high pressure loss valve VH has a larger pressure loss when the hydraulic oil of the same flow rate passes through than the low pressure loss valve VL. Therefore, the pressure flow characteristics of the damping valve V, that is, the combined pressure flow characteristics of the low pressure loss valve VL and the high pressure loss valve VH, are as shown in FIG. 3, and the high pressure is within the range in which the characteristics of the low pressure loss valve VL appear. When the shift to the range in which the characteristics of the loss valve VH appear, the inclination of the pressure flow characteristics becomes large.

なお、本例では、低圧力損失弁ＶＬの閉弁と高圧力損失弁ＶＨの開弁の前後で両者のトータルの流路面積が変化しないように、高圧力損失弁ＶＨにおけるオリフィス溝１３ｄの弁頭側端における断面積を設定してある。よって、合成圧力流量特性は、図３に示すように、低圧力損失弁ＶＬの特性から高圧力損失弁ＶＨの特性への切換わりにおいて圧力変動がない特性となっている。 In this example, the valve of the orifice groove 13d in the high pressure loss valve VH so that the total flow path area of both before and after the closing of the low pressure loss valve VL and the opening of the high pressure loss valve VH does not change. The cross-sectional area at the cranial end is set. Therefore, as shown in FIG. 3, the combined pressure flow rate characteristic has a characteristic that there is no pressure fluctuation when switching from the characteristic of the low pressure loss valve VL to the characteristic of the high pressure loss valve VH.

このように構成された減衰弁Ｖは、図４に示すように、ダンパＤに適用されており、ダンパＤに減衰力を発生させる減衰力発生要素として機能している。 As shown in FIG. 4, the damping valve V configured in this way is applied to the damper D, and functions as a damping force generating element that generates a damping force in the damper D.

以下、ダンパＤの構成について説明する。ダンパＤは、シリンダ２１と、当該シリンダ２１内に摺動自在に挿入されるピストン２２と、シリンダ２１内に移動自在に挿入されてピストン２２に連結されるピストンロッド２３と、シリンダ２１内にピストン２２で区画された伸側室Ｒ１と圧側室Ｒ２と、シリンダ２１の端部に設けたバルブケース２４と、シリンダ２１の外周に設けた外筒２５と、シリンダ２１と外筒２５との間の環状隙間で形成したリザーバＲとを備えている。そして、本例のダンパＤにあっては、ピストン２２とバルブケース２４をそれぞれハウジングとして三つの減衰弁Ｖａ，Ｖｂ，Ｖｃを備えている。 Hereinafter, the configuration of the damper D will be described. The damper D includes a cylinder 21, a piston 22 slidably inserted into the cylinder 21, a piston rod 23 slidably inserted into the cylinder 21 and connected to the piston 22, and a piston in the cylinder 21. The extension side chamber R1 and the compression side chamber R2 partitioned by 22, the valve case 24 provided at the end of the cylinder 21, the outer cylinder 25 provided on the outer periphery of the cylinder 21, and the ring between the cylinder 21 and the outer cylinder 25. It is provided with a reservoir R formed in the gap. The damper D of this example has three damping valves Va, Vb, and Vc with the piston 22 and the valve case 24 as housings, respectively.

また、伸側室Ｒ１と圧側室Ｒ２には、液体として、たとえば、作動油が充填されるとともに、リザーバＲには、作動油のほかに気体が充填されている。液体は、作動油以外にも、水や水溶液なども使用可能である。なお、リザーバＲ内は、特に、気体を圧縮して充填する加圧状態とする必要は無いが、加圧状態としてもよい。 Further, the extension side chamber R1 and the compression side chamber R2 are filled with hydraulic oil as a liquid, for example, and the reservoir R is filled with a gas in addition to the hydraulic oil. As the liquid, water, an aqueous solution, or the like can be used in addition to the hydraulic oil. The inside of the reservoir R does not need to be in a pressurized state in which the gas is compressed and filled, but it may be in a pressurized state.

このダンパＤは、図示はしないが、たとえば、地盤と構造物との間にボールアイソレータや積層ゴム等といった弾性体とともに介装されて免震装置に組み込まれるが、ダンパＤの用途はこれに限定されるものではない。 Although not shown, this damper D is incorporated in a seismic isolation device by being interposed between the ground and a structure together with an elastic body such as a ball isolator or laminated rubber, but the use of the damper D is limited to this. It is not something that is done.

以下、ダンパＤの各部について説明する。シリンダ２１は筒状であって、その図４中右端はバルブケース２４によって閉塞され、図４中左端には環状のロッドガイド２６が取付けられている。また、前記ロッドガイド２６の内周には、シリンダ２１内に移動自在に挿入されるピストンロッド２３が摺動自在に挿入されている。このピストンロッド２３は、本例では、一端をシリンダ２１内に摺動自在に挿入してピストン２２に連結してあり、他端をシリンダ２１外へ突出させていて、シリンダ２１に対して移動自在とされている。本例では、ピストンロッド２３が伸側室Ｒ１のみを貫通していて、ダンパＤは、いわゆる片ロッド型とされている。なお、ダンパＤは、ピストンロッド２３が伸側室Ｒ１および圧側室Ｒ２の双方を貫通してシリンダ２１から両端がシリンダ２１外へ突出する、いわゆる両ロッド型のダンパとされてよい。 Hereinafter, each part of the damper D will be described. The cylinder 21 has a tubular shape, the right end in FIG. 4 is closed by a valve case 24, and an annular rod guide 26 is attached to the left end in FIG. Further, a piston rod 23 that is movably inserted into the cylinder 21 is slidably inserted into the inner circumference of the rod guide 26. In this example, the piston rod 23 has one end slidably inserted into the cylinder 21 and connected to the piston 22, and the other end is projected outside the cylinder 21 so as to be movable with respect to the cylinder 21. It is said that. In this example, the piston rod 23 penetrates only the extension side chamber R1, and the damper D is a so-called single rod type. The damper D may be a so-called double-rod type damper in which the piston rod 23 penetrates both the extension side chamber R1 and the compression side chamber R2 and both ends protrude from the cylinder 21 to the outside of the cylinder 21.

そして、シリンダ２１は、外筒２５内に収容されており、シリンダ２１と外筒２５との間には、リザーバＲが形成されている。また、外筒２５は、この場合有底筒状とされていて、開口端は、前述のロッドガイド２６が取付けられて閉塞されている。さらに、外筒２５の底部とシリンダ２１との間に前記したバルブケース２４が挟持されており、外筒２５内にシリンダ２１及びバルブケース２４が固定されている。 The cylinder 21 is housed in the outer cylinder 25, and a reservoir R is formed between the cylinder 21 and the outer cylinder 25. Further, the outer cylinder 25 has a bottomed tubular shape in this case, and the open end is closed by attaching the rod guide 26 described above. Further, the valve case 24 described above is sandwiched between the bottom of the outer cylinder 25 and the cylinder 21, and the cylinder 21 and the valve case 24 are fixed in the outer cylinder 25.

なお、ピストンロッド２３の図４中左端である他端と、外筒２５の底部には、このダンパＤを構造物と地盤との間の設置箇所へ取付けできるようにブラケット３０，３１が設けられる。 Brackets 30 and 31 are provided at the other end of the piston rod 23, which is the left end in FIG. 4, and at the bottom of the outer cylinder 25 so that the damper D can be attached to an installation location between the structure and the ground. ..

ピストン２２には、減衰弁Ｖａ，Ｖｂがそれぞれ設けられている。具体的には、減衰弁Ｖａ，Ｖｂは、それぞれ、図１に示すように、低圧力損失弁ＶＬと高圧力損失弁ＶＨとで構成されていて、ピストン２２をハウジングＨとしてピストン２２に設けられている。減衰弁Ｖａは、部屋Ａを伸側室Ｒ１とし、部屋Ｂを圧側室Ｒ２として、前述した通りに動作して伸側室Ｒ１から圧側室Ｒ２へ向かう作動油の流れに抵抗を与え、図３の圧力流量特性を示すようになっている。減衰弁Ｖｂは、部屋Ａを圧側室Ｒ２とし、部屋Ｂを伸側室Ｒ１として、前述した通りに動作して圧側室Ｒ２から伸側室Ｒ１へ向かう作動油の流れに抵抗を与え、前述の圧力流量特性を示すようになっている。 The piston 22 is provided with damping valves Va and Vb, respectively. Specifically, as shown in FIG. 1, each of the damping valves Va and Vb is composed of a low pressure loss valve VL and a high pressure loss valve VH, and the piston 22 is provided on the piston 22 as a housing H. ing. The damping valve Va operates as described above with the chamber A as the extension chamber R1 and the chamber B as the compression side chamber R2 to give resistance to the flow of hydraulic oil from the extension chamber R1 to the compression side chamber R2, and the pressure in FIG. It is designed to show the flow rate characteristics. The damping valve Vb operates as described above with the chamber A as the compression side chamber R2 and the chamber B as the extension side chamber R1 to give resistance to the flow of hydraulic oil from the compression side chamber R2 to the extension side chamber R1. It is designed to show characteristics.

さらに、バルブケース２４には、減衰弁Ｖｃが設けられている。具体的には、減衰弁Ｖｃは、図１に示すように、低圧力損失弁ＶＬと高圧力損失弁ＶＨとで構成されていて、バルブケース２４をハウジングＨとしてバルブケース２４に設けられている。減衰弁Ｖｃは、部屋Ａを圧側室Ｒ２とし、部屋ＢをリザーバＲとして、前述した通りに動作して圧側室Ｒ２からリザーバＲへ向かう作動油の流れに抵抗を与え、図３の圧力流量特性を示すようになっている。 Further, the valve case 24 is provided with a damping valve Vc. Specifically, as shown in FIG. 1, the damping valve Vc is composed of a low pressure loss valve VL and a high pressure loss valve VH, and is provided in the valve case 24 with the valve case 24 as the housing H. .. The damping valve Vc operates as described above with the chamber A as the compression side chamber R2 and the chamber B as the reservoir R to give resistance to the flow of hydraulic oil from the compression side chamber R2 to the reservoir R, and the pressure flow rate characteristic of FIG. Is designed to indicate.

また、バルブケース２４には、リザーバＲと圧側室Ｒ２とを連通する吸込通路２７が設けられており、吸込通路２７には、リザーバＲから圧側室Ｒ２へ向かう作動油の流れのみを許容する逆止弁２８が設けられている。 Further, the valve case 24 is provided with a suction passage 27 for communicating the reservoir R and the compression side chamber R2, and the suction passage 27 allows only the flow of hydraulic oil from the reservoir R to the compression side chamber R2. A check valve 28 is provided.

以上のように、ダンパＤは構成され、以下、このダンパＤの作動について説明する。ダンパＤが伸長作動して、ピストン２２が図４中左方へ移動する場合、ピストン２２によって、伸側室Ｒ１が圧縮されて圧側室Ｒ２が拡大される。伸側室Ｒ１の容積減少に見合った量の作動油は、伸側室Ｒ１から押し出されて、減衰弁Ｖａを介して拡大される圧側室Ｒ２へ移動する。ダンパＤの伸長作動の際には、ピストンロッド２３がシリンダ２１内から退出するため、退出するピストンロッド２３の体積分の作動油が吸込通路２７を介してリザーバＲから圧側室Ｒ２へ供給される。 As described above, the damper D is configured, and the operation of the damper D will be described below. When the damper D is extended and the piston 22 moves to the left in FIG. 4, the extension side chamber R1 is compressed by the piston 22 and the compression side chamber R2 is expanded. An amount of hydraulic oil commensurate with the volume reduction of the extension side chamber R1 is pushed out from the extension side chamber R1 and moves to the compression side chamber R2 which is expanded via the damping valve Va. When the damper D is extended, the piston rod 23 exits from the cylinder 21, so that the hydraulic oil corresponding to the volume of the exiting piston rod 23 is supplied from the reservoir R to the compression side chamber R2 via the suction passage 27. ..

そして、減衰弁Ｖａは、図３に示した圧力流量特性を示す。減衰弁Ｖａは、伸側室Ｒ１の圧力と圧側室Ｒ２の圧力の差圧が設定圧Ｐｓ未満の場合、低圧力損失弁ＶＬが開弁して作動油の流れに抵抗を与え、伸側室Ｒ１の圧力と圧側室Ｒ２の圧力の差圧が設定圧Ｐｓ超の場合、高圧力損失弁ＶＨが開弁して作動油の流れに抵抗を与える。そして、ダンパＤの伸長作動時において、減衰弁Ｖａを通過する作動油の流量は、ピストン２２の移動速度に比例する。また、ダンパＤが伸長作動時に発揮する減衰力は、ピストン２２の伸側室Ｒ１に面する断面積と伸側室Ｒ１内の圧力の積からピストン２２の圧側室Ｒ２に面する断面積と圧側室Ｒ２内の圧力の積を差し引いた値となる。よって、ダンパＤの伸長作動時における減衰力特性は、図５に示すが如く、減衰弁Ｖａを通過する流量が流量Ｑｓとなるピストン速度が速度Ｄｖとすると、ピストン速度が速度Ｄｖとなるのを境にして、減衰係数（傾き）が異なる特性となる。具体的には、ダンパＤは、ピストン速度が速度Ｄｖより低いと減衰係数が小さく、ピストン速度が速度Ｄｖより高いと減衰係数が大きくなる減衰力特性を発揮する。 The damping valve Va shows the pressure flow rate characteristics shown in FIG. When the differential pressure between the pressure of the extension side chamber R1 and the pressure of the compression side chamber R2 is less than the set pressure Ps, the damping valve Va opens the low pressure loss valve VL to give resistance to the flow of hydraulic oil, and the extension side chamber R1. When the differential pressure between the pressure and the pressure of the pressure side chamber R2 exceeds the set pressure Ps, the high pressure loss valve VH opens to give resistance to the flow of hydraulic oil. Then, when the damper D is extended, the flow rate of the hydraulic oil passing through the damping valve Va is proportional to the moving speed of the piston 22. Further, the damping force exerted by the damper D during the extension operation is the product of the cross-sectional area of the piston 22 facing the extension side chamber R1 and the pressure in the extension side chamber R1 to the cross-sectional area of the piston 22 facing the compression side chamber R2 and the compression side chamber R2. It is the value obtained by subtracting the product of the pressure inside. Therefore, as shown in FIG. 5, the damping force characteristic at the time of extension operation of the damper D is that the piston speed becomes the speed Dv, where the piston speed at which the flow rate passing through the damping valve Va becomes the flow rate Qs is the speed Dv. At the boundary, the damping coefficient (inclination) is different. Specifically, the damper D exhibits a damping force characteristic in which the damping coefficient is small when the piston speed is lower than the speed Dv, and the damping coefficient is large when the piston speed is higher than the speed Dv.

他方、ダンパＤが収縮作動して、ピストン２２が図４中右方へ移動する場合、ピストン２２によって、圧側室Ｒ２が圧縮されて伸側室Ｒ１が拡大される。圧側室Ｒ２の容積減少によって、伸側室Ｒ１の拡大容積分の作動油は、圧側室Ｒ２から減衰弁Ｖｂを介して拡大される圧側室Ｒ２へ移動する。また、ダンパＤの収縮作動の際には、ピストンロッド２３がシリンダ２１内へ侵入するため、侵入するピストンロッド２３の体積分の作動油は、圧側室Ｒ２から減衰弁Ｖｃを介してリザーバＲへ排出される。 On the other hand, when the damper D contracts and the piston 22 moves to the right in FIG. 4, the compression side chamber R2 is compressed by the piston 22 and the extension side chamber R1 is expanded. Due to the volume reduction of the compression side chamber R2, the hydraulic oil corresponding to the expanded volume of the extension side chamber R1 moves from the compression side chamber R2 to the compression side chamber R2 expanded via the damping valve Vb. Further, since the piston rod 23 enters the cylinder 21 during the contraction operation of the damper D, the hydraulic oil corresponding to the volume of the invading piston rod 23 enters the reservoir R from the compression side chamber R2 via the damping valve Vc. It is discharged.

そして、減衰弁Ｖｂ，Ｖｃは、図３に示した圧力流量特性を示す。そして、ダンパＤの収縮作動時において、減衰弁Ｖｂ，Ｖｃを通過する作動油の流量は、ピストン２２の移動速度に比例する。また、ダンパＤが収縮作動時に発揮する減衰力は、ピストン２２の圧側室Ｒ２に面する断面積と圧側室Ｒ２内の圧力の積からピストン２２の伸側室Ｒ１に面する断面積と伸側室Ｒ１内の圧力の積を差し引いた値となる。そして、減衰弁Ｖｂ，Ｖｃの低圧力損失弁ＶＬの閉弁圧と高圧力損失弁ＶＨの開弁圧である設定圧Ｐｓについては、ダンパＤの収縮作動時における減衰力特性が伸長作動時における減衰力特性と等しくなるようにそれぞれ調整してある。よって、ダンパＤの収縮作動時における減衰力特性も図５に示すが如く、ピストン速度が速度Ｄｖとなるのを境にして、減衰係数が異なる特性となる。具体的には、ダンパＤは、ピストン速度が速度Ｄｖより低いと減衰係数が小さく、ピストン速度が速度Ｄｖより高いと減衰係数が大きくなる減衰力特性を発揮する。 The damping valves Vb and Vc show the pressure flow rate characteristics shown in FIG. Then, when the damper D is contracted, the flow rate of the hydraulic oil passing through the damping valves Vb and Vc is proportional to the moving speed of the piston 22. Further, the damping force exerted by the damper D during the contraction operation is the product of the cross-sectional area of the piston 22 facing the compression side chamber R2 and the pressure in the compression side chamber R2, and the cross-sectional area of the piston 22 facing the extension side chamber R1 and the extension side chamber R1. It is the value obtained by subtracting the product of the pressure inside. Regarding the set pressure Ps, which is the valve closing pressure of the low pressure loss valve VL of the damping valves Vb and Vc and the valve opening pressure of the high pressure loss valve VH, the damping force characteristic at the time of contraction operation of the damper D is at the time of extension operation. Each is adjusted to be equal to the damping force characteristics. Therefore, as shown in FIG. 5, the damping force characteristic at the time of contraction operation of the damper D also has a characteristic that the damping coefficient is different when the piston speed becomes the speed Dv. Specifically, the damper D exhibits a damping force characteristic in which the damping coefficient is small when the piston speed is lower than the speed Dv, and the damping coefficient is large when the piston speed is higher than the speed Dv.

このように減衰弁Ｖは、低圧力損失弁ＶＬと、低圧力損失弁ＶＬと並列に設けられて低圧力損失弁より圧力損失が大きいノーマルクローズ型の高圧力損失弁ＶＨとを備えており、低圧力損失弁ＶＬが上流の圧力の上昇に伴って閉弁するようになっている。 As described above, the damping valve V includes a low pressure loss valve VL and a normally closed type high pressure loss valve VH provided in parallel with the low pressure loss valve VL and having a larger pressure loss than the low pressure loss valve. The low pressure loss valve VL is designed to close as the upstream pressure rises.

このように構成された減衰弁ＶをダンパＤに適用すると、小規模地震動の発生時にはダンパＤの伸縮速度が低く、ダンパＤが発生する減衰力も小さくなる。そのため、ダンパＤは、免震装置の免震効果を阻害せず、地震動を構造物に伝達するのを阻止できる。他方、大規模地震動の発生時にはダンパＤの伸縮速度が高くなるので、ダンパＤが大きな減衰力を発揮して構造物の振動を抑制する。よって、ダンパＤに減衰弁Ｖを適用すると、小規模地震に対して減衰力を小さくし、大規模地震に対して減衰力を大きくするダンパＤを実現できる。 When the damping valve V configured in this way is applied to the damper D, the expansion / contraction speed of the damper D is low when a small-scale earthquake motion occurs, and the damping force generated by the damper D is also small. Therefore, the damper D does not interfere with the seismic isolation effect of the seismic isolation device, and can prevent the seismic motion from being transmitted to the structure. On the other hand, when a large-scale earthquake motion occurs, the expansion / contraction speed of the damper D becomes high, so that the damper D exerts a large damping force to suppress the vibration of the structure. Therefore, when the damping valve V is applied to the damper D, it is possible to realize the damper D in which the damping force is reduced for a small-scale earthquake and the damping force is increased for a large-scale earthquake.

よって、本発明の減衰弁Ｖによれば、免震効果を損なわず、ピストン速度が高速域に達する大振幅の地震動に対して高い減衰力をダンパＤに発揮させえる。また、本発明のダンパＤによれば、免震効果を損なわず、ピストン速度が高速域に達する大振幅の地震動に対して高い減衰力を発揮できる。 Therefore, according to the damping valve V of the present invention, the damper D can exert a high damping force against a large-amplitude seismic motion in which the piston speed reaches a high speed range without impairing the seismic isolation effect. Further, according to the damper D of the present invention, a high damping force can be exhibited against a large-amplitude seismic motion in which the piston speed reaches a high speed range without impairing the seismic isolation effect.

なお、ダンパＤにあっては、減衰弁Ｖｂを廃止して、代わりに圧側室Ｒ２から伸側室Ｒ１へ向かう作動油の流れのみを許容する通路を設ける構造を採用しても、図５に示す減衰力特性を実現できるので、そのようにしてもよい。 In addition, even if the damper D adopts a structure in which the damping valve Vb is abolished and instead a passage for allowing only the flow of hydraulic oil from the compression side chamber R2 to the extension side chamber R1 is adopted, it is shown in FIG. Since the damping force characteristic can be realized, it may be done so.

また、ダンパＤが伸縮作動の際に、シリンダ２１内から作動油がリザーバＲへ必ず排出されるユニフロー型に設定される場合には、伸側室Ｒ１からリザーバＲへ通じる通路の途中に減衰弁Ｖを設ければよい。具体的には、図４に示したダンパＤの構造から、減衰弁Ｖａ，Ｖｂ，Ｖｃを廃止し、その代わりに、圧側室Ｒ２から伸側室Ｒ１へ向かう作動油の流れのみを許容する通路を設ける。さらに、伸側室Ｒ１からリザーバＲへ通じる通路を設けて、この通路に部屋Ａを伸側室Ｒ１に対応させ部屋ＢをリザーバＲに対応させて減衰弁Ｖを設ける。このようにダンパＤを構成すると、伸長時には、圧縮される伸側室Ｒ１からリザーバＲへ減衰弁Ｖを通じて作動油が排出され、拡大する圧側室Ｒ２にはリザーバＲから作動油が供給される。収縮時には、伸側室Ｒ１と圧側室Ｒ２とがピストン２２に設けた通路で連通され、ピストンロッド２３がシリンダ２１内に侵入する体積分の作動油が減衰弁Ｖを介してリザーバＲへ押し出される。よって、このように構成されたダンパＤでは、伸縮作動の際に、必ずシリンダ２１内から作動油が減衰弁Ｖを通じてリザーバＲへ移動し、図５に示す減衰力特性を実現できる。 Further, when the damper D is set to the uniflow type in which the hydraulic oil is always discharged from the inside of the cylinder 21 to the reservoir R when the damper D is expanded and contracted, the damping valve V is in the middle of the passage leading from the extension side chamber R1 to the reservoir R. Should be provided. Specifically, from the structure of the damper D shown in FIG. 4, the damping valves Va, Vb, and Vc are abolished, and instead, a passage that allows only the flow of hydraulic oil from the compression side chamber R2 to the extension side chamber R1 is provided. Provide. Further, a passage leading from the extension side chamber R1 to the reservoir R is provided, and a damping valve V is provided in this passage so that the room A corresponds to the extension side chamber R1 and the room B corresponds to the reservoir R. When the damper D is configured in this way, the hydraulic oil is discharged from the compressed extension side chamber R1 to the reservoir R through the damping valve V at the time of expansion, and the hydraulic oil is supplied from the reservoir R to the expanding compression side chamber R2. At the time of contraction, the extension side chamber R1 and the compression side chamber R2 are communicated with each other through a passage provided in the piston 22, and the volume of hydraulic oil in which the piston rod 23 enters the cylinder 21 is pushed out to the reservoir R via the damping valve V. Therefore, in the damper D configured in this way, the hydraulic oil always moves from the cylinder 21 to the reservoir R through the damping valve V during the expansion / contraction operation, and the damping force characteristic shown in FIG. 5 can be realized.

また、本例の減衰弁Ｖにあっては、高圧力損失弁ＶＨの開弁圧と低圧力損失弁ＶＬの閉弁圧がともに設定圧とされていて、高圧力損失弁ＶＨが低圧力損失弁ＶＬの閉弁とともに開弁するようになっている。よって、本例の減衰弁Ｖにあっては、低圧力損失弁ＶＬと高圧力損失弁ＶＨの流量圧力特性を設定圧で切換できる。したがって、この減衰弁ＶをダンパＤに適用すれば、ダンパＤの減衰係数を設定圧に対応するピストン速度で切換でき、免震装置の設計が非常に容易となる。 Further, in the damping valve V of this example, the valve opening pressure of the high pressure loss valve VH and the valve closing pressure of the low pressure loss valve VL are both set pressures, and the high pressure loss valve VH has a low pressure loss. The valve is opened when the valve VL is closed. Therefore, in the damping valve V of this example, the flow rate and pressure characteristics of the low pressure loss valve VL and the high pressure loss valve VH can be switched by the set pressure. Therefore, if this damping valve V is applied to the damper D, the damping coefficient of the damper D can be switched at the piston speed corresponding to the set pressure, and the design of the seismic isolation device becomes very easy.

なお、高圧力損失弁ＶＨが低圧力損失弁ＶＬの開弁後に開弁し低圧力損失弁ＶＬが閉弁するより前に開弁するように、高圧力損失弁ＶＨの開弁圧を低圧力損失弁ＶＬの開弁圧よりも高く低圧力損失弁ＶＬの閉弁圧よりも低い圧力に設定してもよい。この場合、低圧力損失弁ＶＬと高圧力損失弁ＶＨの特性の切換の際に、低圧力損失弁ＶＬと高圧力損失弁ＶＨの両者が開弁する状況ができるので、図６に示すように、低圧力損失弁ＶＬの特性から高圧力損失弁ＶＨの特性に遷移する際に圧力変動が滑らかとなる。このように構成される減衰弁ＶをダンパＤに適用すれば、減衰係数の切換時において減衰力の変化が滑らかとなるので、免震装置に利用しても構造物へ衝撃を与えずに済む。 The pressure of the high pressure loss valve VH is reduced so that the high pressure loss valve VH opens after the low pressure loss valve VL opens and the low pressure loss valve VL opens before the valve closes. The pressure may be set higher than the valve opening pressure of the loss valve VL and lower than the valve closing pressure of the low pressure loss valve VL. In this case, when the characteristics of the low pressure loss valve VL and the high pressure loss valve VH are switched, both the low pressure loss valve VL and the high pressure loss valve VH can be opened. Therefore, as shown in FIG. The pressure fluctuation becomes smooth when transitioning from the characteristics of the low pressure loss valve VL to the characteristics of the high pressure loss valve VH. If the damping valve V configured in this way is applied to the damper D, the change in damping force becomes smooth when the damping coefficient is switched, so that even if it is used as a seismic isolation device, it does not have to give an impact to the structure. ..

また、本例では、高圧力損失弁ＶＨが低圧力損失弁ＶＬの閉弁の際に、低圧力損失弁ＶＬを通過していた流量を補償するようになっている。つまり、低圧力損失弁ＶＬの閉弁の前後で減衰弁Ｖを通過する流量に変動が生じず、減衰弁Ｖにおける圧力流量特性は、低圧力損失弁ＶＬの閉弁の前後で圧力が急変せず、連続する特性となる。このように構成される減衰弁ＶをダンパＤに適用すれば、減衰係数の切換時において減衰力が急峻に変化しないので、免震装置に利用しても構造物へ衝撃を与えずに済む。 Further, in this example, the high pressure loss valve VH compensates for the flow rate passing through the low pressure loss valve VL when the low pressure loss valve VL is closed. That is, the flow rate passing through the damping valve V does not fluctuate before and after the closing of the low pressure loss valve VL, and the pressure flow rate characteristic of the damping valve V changes suddenly before and after the closing of the low pressure loss valve VL. It becomes a continuous characteristic. If the damping valve V configured in this way is applied to the damper D, the damping force does not change sharply when the damping coefficient is switched, so that even if it is used as a seismic isolation device, it does not give an impact to the structure.

さらに、本例のダンパＤでは、シリンダ２１と、シリンダ２１内に移動自在に挿入されたピストン２２と、シリンダ２１内にピストン２２で区画した伸側室Ｒ１と圧側室Ｒ２と、リザーバＲと、減衰弁Ｖとを備えている。減衰弁Ｖは、伸側室Ｒ１と圧側室Ｒ２との間、伸側室Ｒ１とリザーバＲとの間、および、圧側室Ｒ２とリザーバＲとの間のうち、任意の箇所に設ければよく、このように構成されたダンパＤでは、免震効果を損なわず、ピストン速度が高速域に達する大振幅の地震動に対して高い減衰力を発揮できる。 Further, in the damper D of this example, the cylinder 21, the piston 22 movably inserted into the cylinder 21, the extension side chamber R1 and the compression side chamber R2 partitioned by the piston 22 in the cylinder 21, the reservoir R, and the damping It is equipped with a valve V. The damping valve V may be provided at any position between the extension side chamber R1 and the compression side chamber R2, between the extension side chamber R1 and the reservoir R, and between the compression side chamber R2 and the reservoir R. The damper D configured as described above can exert a high damping force against a large-amplitude seismic motion in which the piston speed reaches a high speed range without impairing the seismic isolation effect.

なお、本例の低圧力損失弁ＶＬと高圧力損失弁ＶＨは、部屋Ａと部屋Ｂの差圧力によって開閉するようになっているが、上流の部屋Ａの圧力のみに依存して開閉するようになっていてもよい。 The low pressure loss valve VL and the high pressure loss valve VH of this example are designed to be opened and closed by the differential pressure between the room A and the room B, but they are opened and closed depending only on the pressure of the upstream room A. It may be.

以上、本発明の好ましい実施の形態を詳細に説明したが、特許請求の範囲から逸脱しない限り、改造、変形及び変更が可能である。 Although the preferred embodiments of the present invention have been described in detail above, modifications, modifications and changes can be made without departing from the scope of claims.

２１・・・シリンダ、２２・・・ピストン、Ｄ・・・ダンパ、Ｒ・・・リザーバ、
Ｒ１・・・伸側室、Ｒ２・・・圧側室、Ｖ・・・減衰弁、ＶＨ・・・高圧力損失弁、ＶＬ・・・低圧力損失弁 21 ... Cylinder, 22 ... Piston, D ... Damper, R ... Reservoir,
R1 ... extension side chamber, R2 ... compression side chamber, V ... damping valve, VH ... high pressure loss valve, VL ... low pressure loss valve

Claims (5)

上流の圧力により開閉し、開弁時に上流から下流への液体の流れを許容する低圧力損失弁と、
前記低圧力損失弁と並列に設けられて、前記低圧力損失弁に比較して同流量の液体の通過時における圧力損失が大きいノーマルクローズ型の高圧力損失弁とを備え、
前記低圧力損失弁は、上流の圧力の上昇に伴って閉弁する
ことを特徴とする減衰弁。 A low pressure loss valve that opens and closes with upstream pressure and allows liquid to flow from upstream to downstream when the valve is opened.
It is provided with a normally closed type high pressure loss valve which is provided in parallel with the low pressure loss valve and has a large pressure loss when passing a liquid of the same flow rate as compared with the low pressure loss valve.
The low pressure loss valve is a damping valve characterized in that the valve closes as the upstream pressure rises. 前記高圧力損失弁は、前記低圧力損失弁の閉弁とともに開弁する
ことを特徴とする請求項１に記載の減衰弁。 The damping valve according to claim 1, wherein the high pressure loss valve is opened together with the closing of the low pressure loss valve. 前記高圧力損失弁は、開弁圧が前記低圧力損失弁の開弁圧よりも高く、前記低圧力損失弁の閉弁圧よりも低い圧力に設定され、前記低圧力損失弁が閉弁するより前に開弁する
ことを特徴とする請求項１に記載の減衰弁。 In the high pressure loss valve, the valve opening pressure is set to be higher than the valve opening pressure of the low pressure loss valve and lower than the valve closing pressure of the low pressure loss valve, and the low pressure loss valve closes. The damping valve according to claim 1, wherein the valve is opened before the valve. 前記高圧力損失弁は、前記低圧力損失弁の閉弁の際に、前記低圧力損失弁を通過していた流量を補償する
ことを特徴とする請求項１から３のいずれか一項に記載の減衰弁。 The invention according to any one of claims 1 to 3, wherein the high pressure loss valve compensates for the flow rate passing through the low pressure loss valve when the low pressure loss valve is closed. Damping valve. シリンダと、
シリンダ内に移動自在に挿入されたピストンと、
前記シリンダ内に前記ピストンで区画した伸側室と圧側室と、
リザーバと、
前記伸側室と前記圧側室との間、前記伸側室と前記リザーバとの間、および、前記圧側室と前記リザーバとの間のうち、任意の箇所に設けた請求項１から４のいずれか一項に記載の減衰弁とを備えた
ことを特徴とするダンパ。 Cylinder and
A piston that is movably inserted into the cylinder,
An extension side chamber and a compression side chamber partitioned by the piston in the cylinder,
Reservoir and
Any one of claims 1 to 4 provided at any position between the extension side chamber and the compression side chamber, between the extension side chamber and the reservoir, and between the compression side chamber and the reservoir. A damper characterized by having the damping valve described in the section.

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